Would a bad CAM shaft cause an engine to misfire?

If a lobe is worn off the camshaft, you'll find that with a compression test. That isn't real common. A broken rocker arm would be more likely. What has you looking in two wildly different directions? Why did you mention a cracked cap? Absolutely that would cause a severe misfire. Once water gets in, any arcing will produce a carbon track which will short out future spark to the affected cylinders.

Have you checked the common stuff first like spark plugs and wires?